A catheter system and corresponding methods are provided for accessing a blood vessel true lumen from a sub-intimal plane of the vessel. The catheter system includes visualization elements for determining the orientation of the true lumen with respect to the sub-intimal plane at an identified entry site...http://www.google.se/patents/US20020103459?utm_source=gb-gplus-sharePatent US20020103459 - Catheter system for vascular re-entry from a sub-intimal space
